net/mlx5e: Nullify table pointer when failing to create

[ Upstream commit 1b540de ]

On failing to create promisc flow steering table, the pointer is
returned with an error. Nullify it so unloading the driver won't try to
destroy a non existing table.

Failing to create promisc table may happen over BF devices when the ARM
side is going through a firmware tear down. The host side start a
reload flow. While the driver unloads, it tries to remove the promisc
table. Remove WARN in this state as it is a valid error flow.

Fixes: 1c46d74 ("net/mlx5e: Optimize promiscuous mode")
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/ethernet/mellanox/mlx5/core/en_fs.c

@@ -783,6 +783,7 @@ static int mlx5e_create_promisc_table(struct mlx5e_flow_steering *fs)
 	ft->t = mlx5_create_auto_grouped_flow_table(fs->ns, &ft_attr);
 	if (IS_ERR(ft->t)) {
 		err = PTR_ERR(ft->t);
+		ft->t = NULL;
 		fs_err(fs, "fail to create promisc table err=%d\n", err);
 		return err;
 	}
@@ -810,7 +811,7 @@ static void mlx5e_del_promisc_rule(struct mlx5e_flow_steering *fs)
 
 static void mlx5e_destroy_promisc_table(struct mlx5e_flow_steering *fs)
 {
-	if (WARN(!fs->promisc.ft.t, "Trying to remove non-existing promiscuous table"))
+	if (!fs->promisc.ft.t)
 		return;
 	mlx5e_del_promisc_rule(fs);
 	mlx5_destroy_flow_table(fs->promisc.ft.t);